|a chattering or flighty, light-headed person.|
|a screen or mat covered with a dark material for shielding a camera lens from excess light or glare.|
|—n , pl -ruses|
|1.||any of a group of submicroscopic entities consisting of a single nucleic acid chain surrounded by a protein coat and capable of replication only within the cells of living organisms: many are pathogenic|
|2.||informal a disease caused by a virus|
|3.||any corrupting or infecting influence|
|4.||computing an unauthorized program that inserts itself into a computer system and then propagates itself to other computers via networks or disks; when activated it interferes with the operation of the computer|
|[C16: from Latin: slime, poisonous liquid; related to Old English wāse marsh, Greek ios poison]|
virus vi·rus (vī'rəs)
n. pl. vi·rus·es
Any of various simple submicroscopic parasites of plants, animals, and bacteria that often cause disease and that consist essentially of a core of RNA or DNA surrounded by a protein coat. Unable to replicate without a host cell, viruses are typically not considered living organisms.
A disease caused by a virus.
|virus (vī'rəs) Pronunciation Key
Microorganisms consisting of DNA and RNA molecules wrapped in a protective coating of proteins. Viruses are the most primitive form of life. They depend on other living cells for their reproduction and growth. (See under “Medicine and Health.”)
Note: Viruses cause many diseases. (See viral infection.)
virusn. [from the obvious analogy with biological viruses, via SF] A cracker program that searches out other programs and `infects' them by embedding a copy of itself in them, so that they become Trojan horses. When these programs are executed, the embedded virus is executed too, thus propagating the `infection'. This normally happens invisibly to the user. Unlike a worm, a virus cannot infect other computers without assistance. It is propagated by vectors such as humans trading programs with their friends (see SEX). The virus may do nothing but propagate itself and then allow the program to run normally. Usually, however, after propagating silently for a while, it starts doing things like writing cute messages on the terminal or playing strange tricks with the display (some viruses include nice display hacks). Many nasty viruses, written by particularly perversely minded crackers, do irreversible damage, like nuking all the user's files.